Human papillomavirus associated cervical lesion: pathogenesis and therapeutic interventions

Abstract Human papillomavirus (HPV) is the most prevalent sexually transmitted virus globally. Persistent high‐risk HPV infection can result in cervical precancerous lesions and cervical cancer, with 70% of cervical cancer cases associated with high‐risk types HPV16 and 18. HPV infection imposes a significant financial and psychological burden. Therefore, studying methods to eradicate HPV infection and halt the progression of precancerous lesions remains crucial. This review comprehensively explores the mechanisms underlying HPV‐related cervical lesions, including the viral life cycle, immune factors, epithelial cell malignant transformation, and host and environmental contributing factors. Additionally, we provide a comprehensive overview of treatment methods for HPV‐related cervical precancerous lesions and cervical cancer. Our focus is on immunotherapy, encompassing HPV therapeutic vaccines, immune checkpoint inhibitors, and advanced adoptive T cell therapy. Furthermore, we summarize the commonly employed drugs and other nonsurgical treatments currently utilized in clinical practice for managing HPV infection and associated cervical lesions. Gene editing technology is currently undergoing clinical research and, although not yet employed officially in clinical treatment of cervical lesions, numerous preclinical studies have substantiated its efficacy. Therefore, it holds promise as a precise treatment strategy for HPV‐related cervical lesions.

The HPV virion exhibits a spherical, unenveloped morphology characterized by a 20-sided cubic symmetry.It comprises an approximately 8 kb circular double-stranded DNA genome enclosed within a protein shell composed of L1 and L2.The virion's diameter ranges from 50 to 60 nm.The genome is organized into three functional sections: the early (E) region (E1-E8), the late (L) region (L1, L2), and the long control region (LCR). 6The E region encodes seven viral nonstructural proteins: E1, E2, E1ˆE4, E5, E6, E7, and E8ˆE2.These proteins are involved in HPV replication, transcription, translation, and transformation.The L region encodes two viral capsid proteins: L1 and L2.The LCR region, also referred to as the upstream regulatory region (URR), does not encode any proteins. 7ersistent HR-HPV infection leads to cervical disease, ultimately progressing to cervical cancer. 8The transformation zone (TZ), located at the junction between the ectocervix and endocervix (squamocolumnar junction), serves as the origin of cervical lesions. 9,10Cervical preneoplasia, also referred to as cervical intraepithelial neoplasia (CIN), is further categorized into CINI, CINII, and CINIII.CINI corresponding to low-grade squamous intraepithelial lesions (LSIL) regresses spontaneously in approximately 80−90% of cases. 11,12During this stage, the virus undergoes active replication, 13 and mild changes occur in cervical epithelial cells.CINII-III corresponds to high-grade squamous intraepithelial lesions (HSIL). 14Despite the relatively low viral replication during this stage, the virus persists due to viral immune evasion, dysregulated vaginal microenvironment, and other cofactors. 15,16Viral oncoproteins expression disrupts the cell cycle, 17 and the viral genome can integrate into the host genome. 18Infected cells proliferate uncontrollably and undergo malignant transformation, 19 ultimately resulting in cervical cancer.
The development of HPV preventive vaccines represents a significant milestone in the prevention and treatment of cervical cancer.These vaccines have demonstrated efficacy in reducing the incidence of cervical cancer and preneoplastic lesions. 20,21However, due to factors such as cost, preventive vaccines have not gained widespread accessibility in economically underdeveloped areas.Furthermore, preventive vaccines have limited efficacy against existing HPV infections and cervical lesions. 22urrently, no specific treatment exists for HPV infection, emphasizing the clearance of infection and reversion of precancerous lesions as the main treatment focus for HPV-related cervical lesions.The standard treatment for cervical cancer remains a combination of surgery and chemoradiotherapy. 23However, patients with advanced, metastatic cervical cancer still face a gloomy clinical prognosis despite undergoing standard therapy. 24In 2014, bevacizumab gained approval for treating metastatic cervical cancer. 25Later, in 2018, pembrolizumab was granted approval for recurrent and metastatic cervical cancer. 26he introduction of these targeted drugs has ignited extensive clinical research, with a particular focus on investigating combinations of targeted drugs, immunomodulatory drugs, and standard radiochemotherapy.The development of these clinical trials and the exploration of novel targeted drugs hold promise for future patients with advanced cervical cancer.
This review presents a comprehensive summary of the molecular and cellular pathogenesis of HPV-related cervical lesions.It encompasses the viral life cycle, immune factors, epithelial cell malignant transformation, and contributions from the host and environment.The goal is to offer a detailed elucidation of the pathogenic mechanisms underlying HPV-related cervical lesions.Additionally, we examine nonsurgical treatments for HPV-associated cervical preneoplastic lesions and cervical cancer.Surgical interventions and radiation or chemotherapy fall outside the scope of this review and are not covered.Our focus lies on immunotherapy, encompassing HPV therapeutic vaccines, immune checkpoint inhibitors, and advanced adoptive T cell (ATC) therapy.These strategies hold potential for introducing novel treatment avenues when integrated with standard-of-care approaches.Furthermore, we outline frequently used drugs and other nonsurgical treatments currently employed in clinical practice for managing HPV infection and precancerous lesions.Moreover, emerging gene editing technology has exhibited effectiveness in numerous preclinical studies, showing promise as a precise treatment strategy for HPV-related cervical lesions.This comprehensive review aspires to provide valuable references for clinical and preclinical research on HPV-associated cervical lesions in the future.

Life cycle of HPV
HPV targets the basal layer of the stratified squamous epithelium.After entering the host cell, it initiates initial replication and differentiation-induced replication, culminating in the assembly and release of viral particles within the upper epithelial cells.Comprehending the virus's life cycle and the pertinent host factors is paramount for treating HPV infection (Figure 1).The HPV life cycle commences with the infection of cells in the basal layer of the stratified squamous epithelium, which occurs due to disruptions in the epithelial barrier caused by minor injuries.In the normal epithelium, the basal cells represent the sole proliferating cells, in contrast to the differentiated cells in the upper layer have exited the cell cycle. 27In the initial infection stage, the virus F I G U R E 1 Life cycle of human papillomavirus.HPV entry to the basal cells, once it enters into the cells, HPV initiates its genome replication, which is mainly dependent on the E1 and E2 proteins; the expression of E6 and E7 contributes to promote host cell replication and prevent apoptosis.With the differentiation of epithelial cells, the HPV capsid proteins L1 and L2 express on the upper epithelial cells and complete the assembly and release of viral particles.
traverses cellular barriers, including the plasma membrane and the nuclear envelope.This process is known as virus entry.For HPV16, the virus initiates its interaction by binding to heparan sulfate proteoglycans (HSPGs) on the epithelial cell surface and basement membrane (BM) via the L1 major capsid protein.][30] HPV enters the cytoplasm through independent endocytosis.Following cytoplasmic entry, the HPV capsid undergoes uncoating during acid endocytosis, a process that can be facilitated by host cell cyclophilin, 31 heterotetrameric annexin A2/S100A10 (A2t), 32 and other factors.HPV enters the endosome and subsequently traffics to the trans-Golgi network and Golgi apparatus.The virus must traverse these compartments to reach the nucleus and initiate infection.4][35][36] Cell-penetrating peptides facilitate the insertion of L2 into the endosome membrane. 37,38Subsequently, retromer recruitment ensures stable transient membrane insertion of the L2 capsid protein. 39,40This step is pivotal for productive trafficking.γ-Secretase can promote L2 membrane insertion. 39The GTPase-activating protein folliculin safeguards incoming HPV virions from lysosomal degradation, 41 similar to the role of coat protein complex I. 42 The virus remains within in the Golgi until cell cycle progression into mitosis, when the breakdown of the nuclear membrane facilitates the accumulation of viral DNA at promyelocytic leukemia nuclear bodies, where is the site of viral transcription and replication. 31,37,43However, the process of intranuclear delivery and the cellular proteins involved in these steps remain uncertain.Several proteins, such as Ran-binding protein 10, karyopherin alpha, and dynein light chain DYNLT3, can bind to L2 and assist in its transport toward mitotic chromatin. 36Rizzato's study demonstrated that the CDK1 and PLK1 sequentially phosphorylate the chromosome binding region of L2 to regulate the delivery of HPV viral DNA to mitotic chromatin during mitosis. 44Additionally, the autophagy adaptor p62 may also have involvement in the nuclear delivery process. 43Numerous studies have investigated the mechanism of HPV entry.However, most of these studies have concentrated on the function of individual or a limited number of proteins, and the precise process remains incompletely understood.
Following successful delivery, the viral genome undergoes amplification during the establishment phase.During the initial replication stage, the viral genome maintains at 20−50 copies per cell, and this count remains stable during cell proliferation in HPV-infected cells.6][47] E2, functioning as a DNA binding factor, binds to the palindromic DNA sequences within the LCR that surrounds the viral origin of replication.9][50] Nonetheless, E1 does not appear to be indispensable for the initial replication. 51E1 and E2 are the sole two virus-encoded proteins required for DNA replication.The remaining replication proteins are derived from the host cellular DNA replication machinery.3][54][55][56] Phosphorylation of E2 by CK2 enhances its interaction with TOBP1, enabling the localization of the viral genome to chromatin sites that support viral replication during mitosis.8][59] The E2 protein binds to both the viral genome and host chromatin simultaneously, ensuring the retention of viral genomes in daughter nuclei upon the completion of mitosis. 58This function is termed the plasmid segregation function of the E2 protein, which is pivotal for sustaining the episomal genome. 59In the initial stage, virus protein E6/E7 expression is restricted, 27 a modest level of E6/E7 is enough to target P53 and PRb, fostering cell proliferation to support virus replication.
The viral life cycle correlates with the differentiation of infected cells, during which the virus migrates from the basal layer to the spinous layer, triggering the late stage of the viral life cycle.This stage involves vegetative genome replication and the expression of the capsid proteins L1 and L2.Though the mechanism underlying the elevation in HPV DNA synthesis remains unclear, it appears to be linked to the downregulation of the CCCTCbinding factor-associated Yin Yang1 transcription factor. 60dditionally, disruptions in viral genome looping and loss of epigenetic repression of viral enhancer activity 27 may be contributing factors.The upregulation of E6/E7 expression and downregulation of E2 ˆE8 expression also promote genome replication. 61Murakami et al.'s 62 research demonstrated that nucleosome positioning and its chemical and compositional modifications may have essential roles in genome regulation.
Regarding the mechanism of virus genome replication, in the initial infection stage, the HPV genome undergoes E1-and E2-dependent bidirectional replication, which is essential for maintaining genome integrity.This replication process can be regulated by the Werner helicase. 63s the viral genomes oligomerize, the virus genome starts replicating through break-induced replication (BIR).BIR becomes activated under stress conditions to repair double-strand breaks and collapsed classical replication forks. 64HPV oncoproteins trigger the activation ATR and ATM pathways by inducing a substantial count of DNA breaks. 65Furthermore, they recruit DNA damage factors, such as pATM and pCh2, 66 to promote the viral genome replication.][69] Enhanced read-through at the early HPV16 polyadenylation signal into the late region of the HPV16 genome results in HPV late gene expression, leading to the production of HPV16 late L2 mRNAs. 70Following the activation of late promoters, the expression of L1 and L2 ensues, ultimately leading to the complete formation of virions.This process occurs in the upper epithelial layers, allowing the virus to complete its life cycle and consequently leading to the development of benign or malignant proliferative lesions of the cervix.

Immune evasion and persistent HPV infection
The majority of HPV infections are resolved within 1−2 years.However, persistent HPV infection can lead to cervical lesions and ultimately cervical cancer.Various mechanisms of immune evasion induced by HPV can lead to immune tolerance, enabling persistent HPV infection.Patients with HPV-related cervical lesions exhibit an immunosuppressed microenvironment.Additionally, individuals with HIV are more prone to developing HPV infection and HPV-related cervical lesions, providing further evidence of the immune factors in the development of HPV-related cervical lesions.
In normal women, HPV infection can be eliminated through innate and adaptive immune responses, with only a small portion of HPV infections becoming persistent.Innate immune response, mounted by dendritic cells (DCs), macrophages, natural killer cells, and natural killer T cells, which serve as the first line of defense against HPV infection. 71The subsequent defense entails cytotoxic T lymphocytes (CTLs) targeting the HPV oncoprotein appears to eliminate HPV-infected cells.However, HR-HPV have developed various mechanisms to evade the host's immune response.

Innate immune response
HPV can influence the pattern recognition receptors (PRRs) and downstream pathways, thus disrupting virus recognition and inhibiting interferon (IFN) responses.It can also impact the functionality of innate immune cells and modulate cytokine expression, which is not beneficial for virus clearance.Both innate immune cells and keratinocytes possess the ability to express PRRs capable of identifying microbial pathogens and damage-associated signals, including molecular patterns and damage-associated molecular patterns.These PRRs encompass Toll-like receptors (TLRs), nucleotide binding oligomerization domain-like receptors (NLRs), retinoic acid-inducible gene-I-like receptors (RLRs), and cytosolic DNA sensors. 15They constitute the first line of defense against foreign invaders.Suppression of the expression of PRRs and alteration of downstream cascades can both contribute to immune evasion.In the context of HPV16 infection, there is an alteration in the expression of TLRs.After infection, TLR2 and TLR7 are significantly downregulated, while the TLR4 is conversed regulated. 72Cytosolic DNA sensors IFI16 and STING are found to be upregulated after HPV infection.During the early stage of HPV life cycle, the virus can evade the cGAS/STING surveillance through vesicular trafficking. 73dditionally, HPV16 E6 can inhibit the dsRNA sensor RIG-I by promoting the degradation of TRIM25. 74HPVE5 can inhibit both the cGAS-STING and the RIG-I/MDA5 axis, effectively suppressing the virus recognition machinery. 75he IFN response constitutes a pivotal facet of host's innate immune.Most type I IFNs are induced through the binding of viral products to PRRs, activating IFN factors (IRFs) and NF-κB, which subsequently stimulate the synthesis of IFN molecules. 76,77Type I IFNs facilitate the phosphorylation and dimerization of signal transducer and activator of transcription1 (STAT1) and STAT2 upon binding to the type I receptor.This process induces the transcription of IFN-stimulated genes (ISGs), thereby impeding viral replication and spread.HPV can hinder the IFN response by affecting PRRs.cGAS/STING can induce IRF3-depedent antiviral IFN production upon sensing cytosolic DNA, 78 while HPV16 can degrade STING through NLRX1 mediation, thereby impacting the IFN response. 79irus oncoproteins can directly disrupt key modules and genes to evade the IFN response.The E1 protein can downregulate immune response genes, including IFNβ1 and IFNλ1 and ISG. 80E6 and E7 also appear to collaboratively repress the transcription of ISG. 81,82Furthermore, both E6 and E7 employ distinct mechanisms to target the IFN signaling pathway.E7 can bind to and inhibit the transactivating function of IRF1 and can mediate transcription activation of chromatin repressor SUV39H1.This action promotes the epigenetic silencing of RIG-1, cGAS, and STING, effectively halting IFN secretion. 83eanwhile, E6 binds to IRF3, suppressing its transcriptional activity, and it can also disrupt JAK-STAT activation by binding to Tyk2. 81,84HPV16 E5 has been observed to suppress the IFN signal in both infected cells and stromal microenvironment. 85This suppression potentially involves EGFR and TGFBR2 signaling pathways. 86PV impacts the migration, maturation, and differentiation of innate immunes cells.DCs represent the pivotal mediators of innate immunity.HPV16 E2 can hinder the migrations of DCs by inducing overproduction of prostaglandin E2. 87 HPV E6 can downregulate CD40 through E6/p53/AKNA (AT-Hook Transcription Factor) axis, thereby influencing the function of DCs. 88In early cervical lesions, HPV16 and 18 can impede the increased natural killer cells, with the effect of HPV16 proving more pronounced. 89Researchers found that the inhibitory molecules TIGIT and KLRG1 on NK cells increased in HPV16-associated cervical lesions, thereby impacting NK cell-mediated immune responses. 90PV viral oncoproteins can modulate the production of several cytokines, thus influencing both innate and adaptive immunity. 91HPV16 E6/E7 can obstruct the production of IL-1β by inhibiting the binding of IRF6 on the IL-1β promoter, which is critical in host defenses against injury and infection. 92The IL-17 family cytokines play an important protective role in immunes response, while the level of IL-17 was found to be low in HPVinfected patients. 93HPVE6/E7 also downregulate the IL-2 and impact HPV clearance. 94Additionally, both E6/E7 and E6* from HR-HPV can elevate the expression of IL-6 in keratinocytes, fostering a proinflammatory microenvironment that facilitates the progression of cervical lesions. 95urthermore, it was found that E7 can interact with several core members (NEMO, CK1, and β-TrCP) of both the NF-κB and Wnt/β-catenin signaling pathways, effectively inhibiting host defense peptide expression. 96Moreover, HPV can elevate the expression of human leukocyte antigen (HLA)-G, favoring infected cells to escape detection by immune surveillance cells and promoting the persistence of HPV. 97

Adaptive immune response
Antigen-presenting cells (APCs) play a crucial role in initiating adaptive immunity by presenting the antigen to CD4+ T help and CD8+ CTLs through major histocompatibility complex (MHC) II and MHC I molecules, respectively.In addition to their effects on DC differentiation and proliferation within the context of innate immunity, HPV oncoproteins can also impact adaptive immunity by influencing antigen presentation.Specifically, HPV16 E6 can impair the function of the transporter associated with antigen-processing complex. 98he persistence of HPV infection largely depends on the composition of T cell subsets within the tumor microenvironment.Infiltration of T cells that suppress tumor growth can impede cancer progression, while the opposite outcome is also plausible.Effective CTL responses frequently rely on support from T helper cell.Impairment of the T helper cell response can lead to CD8+ T-cell exhaustion and failure, impeding the resolution of persistent infection.Bashaw's study demonstrated that HPV16 E7-driven epithelial hyperplasia can attenuate Th1 immunity and steer T-cell differentiation toward a regulatory or anergic phenotype. 99Furthermore, E7-mediated epithelial hyperplasia can augment the population of peripheral regulatory T cells and suppress antigen-specific CD8+T-cells. 100,101eports indicate that IFI16 can elevate PD-L1 through STING-TBK1-NF-κB pathway, thus aiding cells in evading immune attack. 102HPV E6 and E7 can also increase PD-L1 expression through miR-142-5p/PD-L1 axis. 103Additionally, in HPV-associated cervical cancer, the m6A regulator METTL3 was found to be upregulated and promote the expression of PD-1, 104 which can hinder the cytotoxic of CD8+T cells.The role of humoral immunity in viral clearance primarily depends on antibody production.In the life cycle of HPV, the expression of L1 and L2 is restricted to the upper epithelial layers, leading to delayed immune recognition. 105In the cases of mastomys natalensis papillomavirus, researchers found that virus express different L1 isoforms to escape adaptive immune responses.During the early stages of HPV infection, the virus employs an extended version of the L1 protein to elude immune system detection.This strategy capitalizes on the fact that antibodies recognizing the lengthier L1 protein lack neutralizing capacity and are incapable of hindering virus dissemination.Consequently, the virus is afforded ample time to establish infection. 106

Pyroptosis
Pyroptosis, a profoundly inflammatory mode of programmed cell death, can be incited by inflammasomes and serves as a defense mechanism against pathogenic infection.Researchers found that HPV E7 can inhibit cell pyroptosis by facilitating TRIM21-mediated degradation and ubiquitination of the IFI16 inflammasome, which also contributes to an essential immune evasion strategy. 107

Malignant transformation of HPV-infected cells
The development of cervical lesions entails molecular modifications beyond persistent HR-HPVs infection.Changes in these molecules result in alterations in cell phenotypes, encompassing cell cycle regulation, proliferation, death, adhesion, and aggressiveness.Moreover, modifications in the host genome both form the basis of molecular changes and engage with them.Over time, these aberrant cell phenotypes gradually accumulate, propelled by abnormal cell metabolism and oxidative stress.Subsequently, cells undergo a progressive malignant transformation, eventually leading to the onset of cancer (Figure 2).

2.3.1
Abnormal regulation of the cell cycle and malignant cell proliferation Human cells undergo mitosis to ensure the preservation of chromosomal stability in progeny cells.The cell cycle encompasses the complete process from the completion of one division to the conclusion of the subsequent division.It is divided into interphase and division phase.Interphase is subdivided into three stages: G1 phase, S phase, and G2 phase.The M phase or mitosis, during which DNA replication occurs in the S phase.The cell cycle is governed by five checkpoints: G1/S phase checkpoint, S phase checkpoint, G2/M phase checkpoint, DNA replication checkpoints, and spindle assembly checkpoints.These checkpoints can temporarily arrest the cell cycle, enabling genetic information editing, repair, or induce apoptosis.HPV disrupts checkpoint integrity, granting cells multiple re-entries into the cycle, fostering malignant cell proliferation.Cell cycle regulation occurs at the downstream level, while abnormal alterations in upstream signaling pathways and host proteins involved in cell proliferation can also contribute to abnormal cell proliferation and malignant transformation.Additionally, HPV can modulate cell proliferation by upregulating or downregulating specific noncoding RNAs.Malignant cell proliferation is a crucial characteristic in the malignant transformation of normal cells, which significantly enhances comprehension of HPV-triggered cervical lesions and cervical cancer pathogenesis.

Dysregulation of cell cycle-related proteins
Proper cell cycle regulation relies on diverse proteins, including cyclins and cyclin-dependent kinases (CDKs), cyclin-dependent kinase inhibitors (CKIs), the retinoblastoma protein (RB) family, the E2F transcription factor family, and the p53 family.Dysregulation of these proteins has been noted in HPV-infected cells, leading to aberrant cell cycle entry and unrestrained proliferation.
Cyclins and CDKs: The proper progression of the cell cycle relies on the interplay between cyclins and CDKs, cyclins coordinate the progress of the cell cycle by binding to CDKs.Elevated Cyclin D1 expression has been observed in specific SILs arising from persistent HR-HPV infection in cervical epithelial cells. 108However, the precise mechanism underlying this dysregulation remains unclear.Researchers have discovered that E6 can enhance AurA expression, and their interaction can influence the expression of cyclin E and phosphorylated Histone H3.These proteins play vital roles in the G1/S and mitotic phases, disrupting cell cycle regulation in HPV-positive cells. 109 I G U R E 2 Pathogenesis of HPV infection-related cervical lesion.Under persistent HPV infection, cervical lesion progress from preneoplastic lesions (CINII-III) to cervical cancer.During this progress, besides immune factors, the cervical cells undergo a series of malignant transformation because of the virus oncoproteins and gene, including malignant proliferation, cellular senescence, apoptosis inhibited, increased cell metastasis and invasion, and HPV genome integration.The contributing factors, such as vaginal dysbiosis and others, work together, leading to the progression of cervical lesion and cervical cancer finally.
CKI family: CKIs hold pivotal roles in regulating cell cycle progression.The Kip/Cip family, which includes three structurally related proteins (p21, p27, and p57), and the INK4 protein family, consisting of four related proteins (p16, p15, p18, and p19), constitute critical CKI families.HPV oncoproteins can directly or indirectly influence CKIs.HR-HPV has the capacity to selectively recruit USP46, a cellular deubiquitinase that stabilizes Cdt2 that can regulate the S phase of the cell cycle by degrading p21, Set8, and Cdt. 110Although p16 generally functions as a tumor suppressor, in HPV-transformed cervical cancer, E7 facilitates the degradation of Rb.As a result, p16 exhibits oncogenic activity, fostering cervical carcinoma proliferation through the CDK-HuR-IL1A axis. 111b family and E2F transcription factors family: The human family of E2F transcription factors primarily regulated by the RB protein family, comprising RB1 (pRb), RBL1 (p107), and RBL2 (p130).Phosphorylated retinoblastoma protein (pRb) functions as a pivotal rate-limiting factor for cyclin-CDK complex-mediated phosphorylation during the G1 phase, constituting a central element of the G1/S regulatory checkpoint.pRb liberate bound E2Fs, allowing unbound E2F to translocate to the nucleus, where it engages with gene promoter regions possessing specific sequences, such as c-myc, the promoter region of the E2F-1 gene.This engagement facilitates genes expression.HPV16/18 can disrupt nuclear localization of p130, contributing to cell cycle deregulation.112 RB-like proteins p107 and p130 facilitate the formation of DREAMC, a multisubunit DNA binding complex that acts as an evolutionarily conserved transcriptional repressor, impeding cell-cycleregulated genes transcription.113 E2F1 is pivotal in G1/S checkpoint.E7 can enhance the expression of general control nondepressible 5, which regulates the expression of E2F1 by acetylating H3K9 in the E2F1 promoter.114,115 In cervical cancer cells, the E7 oncoprotein propels proliferation through E2F.116 P53 family: The tumor suppressor p53 stimulates the expression of p21, culminating in G1 phase cell cycle arrest.The degradation of p53 is a hallmark of α-HPVs and HPV-associated carcinogenesis.The E6 oncoprotein forms a ternary complex with the E3 ubiquitin ligase E6associated protein (E6AP) and tumor suppressor protein p53, leading to the ubiquitination of p53.117,118 Abnormal nuclear export of HP1γ, mediated by exportin-1, is responsible for E6-mediated degradation of p53.119 In specific contexts, tumor suppressors can exhibit proproliferation functions.Researchers discovered that HPV38 E6 and E7 induce the accumulation of a wild-type p53 form in human keratinocytes (HKs), promoting cellular proliferation.120 Others: Recent studies have unveiled the anaphasepromoting complex/cyclosome (APC/C) coactivator, Cdh1, as a new target of E7.APC/C is responsible for targeting various cell cycle-related proteins.The activity of APC/C-Cdh1 spans from anaphase to cytokinesis and extends until the G1 phase.Inactivation of Cdh1 induced by HPV16 E7 disrupts the function of APC/C, leading to the abnormal accumulation of Cdh1 substrates, such as FoxM1.121 This accumulation can impede CKIs, which are frequently overexpressed in diverse malignancies and further augmenting cell proliferation.

Abnormal transduction of cell signaling and cell proliferation
The regulation of the cell occurs at the downstream level, and alterations in the upstream pathways can impact cell cycle regulation and cell proliferation, either directly or indirectly.
Notch signaling pathway: The Notch signaling pathway, critical for the growth of mammalian epithelial cells, constitutes a conserved cascade consisting of Notch receptors, Notch ligands, DSL proteins (Delta, Serrate, LAG), CSL (CBF-1, suppressor of hairless, lag), DNA-binding proteins, and other regulatory molecules. 122This pathway targets genes such as Cyclin D and CDK2.HPV16 selectively modulates delta-like ligand (DLL)-Notch1 signaling, propelling squamous cell proliferation.Additionally, HPV E6 induces sustained DLL4 expression in keratinocytes, promoting proliferation while limiting keratinocyte differentiation through downregulation of DLL1. 123Different HPV-E6 genera appear to exhibit varying Notch signaling pathway activation.β HPV E6 proteins repress Notch reporter expression, with HPV38 E6 displaying notable repression potential.In contrast, α-HPV E6, particularly HPV16, prominently activates reporter expression, while HPV18 E6 yields no discernible effect.This diversity in Notch pathway targeting might bear implications for potential HPV therapies. 124nt signaling pathway: The Wnt signaling encompasses three routes: Wnt /β-catenin, Wnt /Ca 2+ , and Wnt /pcp pathways.The Wnt /β-catenin pathway represents the classical pathway of Wnt signaling.Cyclin D and cyclin E are the downstream target genes of Wnt signaling.Activation of the Wnt pathway increases cytoplasmic β-catenin, subsequently fueling the activation of cyclin genes, culminating in cellular division, growth, and uncontrolled proliferation.HPV18 E6 diminishes MAGI3 levels, contributing to Wnt /β-catenin signaling activation.125 E6 proteins from HR-HPV and LR-HPV activate the Wnt/ β-catenin pathway by degrading NHERF1 through E6AP.126 Besides, HPV-18 E6 oncoprotein and its spliced isoform E6*I regulate the Wnt/β-catenin cell signaling pathway through upregulating TCF-4 transcriptional factors.127 In addition to activating the classical Wnt pathways, HPV oncoproteins also activate nonclassical pathways.Research demonstrates that E6 preferentially augments the translation of WNT4, JIP1, and JIP2, thereby engendering noncanonical WNT/PCP/JNK pathway activation, fostering in vitro cell proliferation.128 Wnt signaling interfaces with diverse signaling pathways, yet several facets of these interactions remain enigmatic and warrant further investigation.The formulation of efficacious anticancer agents grounded in pathway mechanisms stands as a promising avenue for future research.
HIPPO signaling pathway: Extensive investigations have demonstrated that the HIPPO signaling pathway is a tumor-suppressive pathway that meticulously governs cell proliferation and plays a significant role across distinct cancer development stages.Yes-associated protein (YAP), a pivotal effector molecule of HIPPO, phosphorylates the transcriptional coactivator YAP and its homologous protein TAZ, ushering their cytosolic sequestration and degradation.Conversely, nonphosphorylated YAP/TAZ enters the nucleus and binds to the TEAD family and other transcriptional activators, activating the expression of target genes and promoting cell proliferation while suppressing apoptosis.The roster of YAP target genes includes cyclins and E2Fs, governing the cell cycle.YAP and TAZ concurrently serve as coactivators of cell proliferation-associated genes, including CCN1 and MYC.The upregulation of E6/E7 in human cells downregulates PTPN14, 129 thereby catalyzing YAP1 activation through LATS2 upregulation. 130,131This configuration establishes a negative feedback loop pivotal for sustaining cervical epithelial cell homeostasis.However, HR-HPV targets LATS2, perturbing the feedback loop and fostering the malignant transformation of cervical epithelial cells1. 132he dimeric conformation of HPV E6 assumes a critical function in the elevation of YAP/TAZ. 133I3K/AKT signaling pathway: The PI3K/AKT signaling pathway plays a crucial role in regulating cell proliferation, differentiation, and migration, substantiating its involvement across numerous HPV-associated cancers.134 AKT regulates the cell cycle by acting on downstream substrates, including CDKs, cyclins, and CKIs, thereby collectively orchestrating the regulation of cell proliferation.Notably, HPV triggers the upregulation of nuclear receptor-related-1 protein, which autonomously triggers the PI3K/Akt/mTOR signaling cascade, precipitating cell proliferation.135 HPVE7 orchestrates the aberrant expression of Non-SMC (Structural Maintenance of Chromosomes) condensin I complex subunit H, consequently activating the PI3K/Akt/SGK pathway.This activation culminates in the proliferation, EMT, and invasion of HPVinfected cells, further promoting the emergence of cervical lesions.136 In HPVE7-expressing cells, the activation of PI3K/AKT/mTOR promotes the serine 11 (S11) phosphorylation of chromosome condensation1, facilitating G1/S transition of HPV-infected cells.137 Sustained expression of HPV16 E7 augments the expression of p-AKT/P-Src, propelling the progression of cervical precancerous lesions.138 RAS signaling pathway: The RAS pathway includes three classical conduits: RAF-MEK-ERK (MAPK), PI3K-Akt-mTOR, and RAL-GEF pathways, which play crucial roles in cell proliferation, survival, and differentiation.Abnormal regulation of the RAS pathway is intrinsically tied to the emergence of various tumors. Stues have shown that HPV oncoproteins can promote the malignant proliferation of HPV-infected cells by modulating signaling pathways and the expression of upstream and downstream molecules.For instance, HPV8 E6 selectively targets protein-tyrosine-phosphatase H1, thereby instigating the sustained proliferation of keratinocytes by activating Ras.139

Host target proteins involved in cell proliferation
Telomerase, which is activated in all HPV-associated cancers, can elongate telomeric DNA, hinder senscence and apoptosis, and bestow cell immortality.The ratedetermining factor for telomerase is the expression of its catalytic subunit, hTERT. 140HR-HPVE6 relies on multiple cellular proteins, including NFX1-123, which is upregulated in HPV16-positive cervical cancer to regulate the activity of hTERT and telomerase. 141,142HPV16 E6 binds to the promoter region of hTERT, inducing its expression and ultimatly activating the function of telomerase. 143ecently, researchers have found that HPVE6 interaction with AuyB, enhances hTERT expression and augments telomerase activity. 144n addition to telomerase, HPV oncoproteins engaget with other small molecule proteins to govern cell proliferation.Eukaryotic translation initiation factors facilitate protein synthesis, promoting cell proliferation by aiding the transfer of specific mRNAs and the expression of genes related to cell cycle regulation.Some of these genes are related to cell cycle-related proteins.Studies have demonstrated that HPVE6 upregulates the expression of eIF5A-1 145 and modulates the activity of eIF4E protein through the MEK/ERK and AKT/PKB pathways. 146HPV16 E7 increases the expression of pyruvate kinaseM2 (PKM2) and trriggers its nonglycolytic function, fostering cervical cancer cell proliferation. 147HPV18 E7 enhances the transcription of ELK-1, an activator that stimulates cell proliferation. 148HPV16 E6 upregulates silent information regulator1, promoting cervical cell proliferation. 149Knockdown of AIB7 expression in E1E6 immortalized human cervical cells significantly inhibits cell proliferation, underscoring AIB1 as a promising target for HPV E6 and a biomarker for cervical cancer progression. 150ncoding RNA and cell proliferation Noncoding RNAs such as microRNA (miRNA) and long noncoding RNA (lncRNA) also participate the regulation of cell proliferation.miRNA are a class of short regulatory noncoding RNAs, approximately 22 nucleotides long.They exert negative control over target gene expression and cellular processes, including differentiation, proliferation, and apoptosis, chiefly through the promotion of mRNA degradation or translational repression.lncR-NAs are noncoding RNAs exceeding 200 nucleotides in length, undertaking a regulatory role in gene expression.Recent studies have revealed that lncRNAs assume either cancer-promoting or cancer-suppressing roles in tumor initiation and progression.They actively participate in the regulation of apoptosis, tumor invasion, and metastasis.In HPV-infected cells, the HPV oncoproteins, especially E6 and E7, possess the capability to influence numerous noncoding RNAs, thus fostering processes such as promoting cell proliferation, migration, and invasion (Table 1).

Cellular senescence, apoptosis, and autophagy
Cellular senescence, apoptosis, and autophagy play a significant role in HPV-related cervical lesions.HPV oncoproteins can disrupt the equilibrium of cell numbers by modulating molecules and signaling pathways associated with these processes.This leads to the buildup of aberrant cells and the facilitation of malignant transformation.
Cellular senescence is a common phenomenon in the biological realm.Aging can induce irreversible cell cycle arrest, acknowledged as an autonomous tumor suppression mechanism.Suppression of cell senescence can promote uncontrolled cell proliferation, ultimately contribute to malignant alterations.Activation of the DNA damage response triggers P53-mediated cellular senescence.However, the E2 protein can bind to P53, attenuating its ability to induce cellular senescence in response to DNA damage. 167Notably, the HPV-18 E2 protein can downregulate antisense noncoding mitochondrial RNA-2, consequently delaying replicative senescence in HKs. 168issue cells maintain a quantitative balance through the interplay of proliferation and apoptosis.Disruption of this balance can contribute to the development of diseases, including cancer.Currently, apoptosis in eukaryotic cells is predominantly mediated by the death receptormediated extrinsic pathway, the mitochondrial intrinsic pathway, the B-granidase-mediated pathway, and the nearendoplasmic reticulum stress pathway.The composition of the apoptosis mechanism mainly involves four protein families: apoptosis proteases (caspases), adapter proteins, TA B L E 1 Noncoding RNA modulated by HPV oncoproteins related to cell proliferation.Bcl-2 family proteins, and apoptosis inhibitory proteins.HPV E6 targets apoptosis-inducing factor (AIF) for degradation, thereby obstructing AIF-mediated apoptosis. 169dditionally, HPV16 E6 disrupts apoptosis by deregulating death domain-associated protein and suppressing caspase-8 activities. 170Furthermore, HPVE6 downregulates nuclear transport, impairing IFN-γ-dependent apoptosis. 171Moreover, HPVE1/E6 upregulates UHRF7, which suppresses the expression of tumor-suppressor genes (TSGs), allowing cells to evade apoptosis and promoting cancer progression. 172The innate immune receptor NOD1 also participates in the apoptotic signaling pathway, but it can be downregulated by HPV E6/E7, inhibiting apoptosis of cancer cells. 173Recently, researchers have reported that lncRNA HIF1A-AS2, regulated by HPV16 E6, restrains apoptosis in cervical cancer cells through the P53/Caspase 9/Caspase 3 axis. 174utophagy involves the phagocytosis and degradation of damaged or redundant cell components, such as aging proteins and organelles, ultimately promoting cell survival.However, excessive autophagy can exhaust intracellular proteins and energy to an extent where cell viability is compromised, leading to apoptosis.Autophagy exhibits a dual role in cancer development.During the early stages of cell transformation, autophagy inhibits the generation of cancer cells.However, once cancer cells are established, autophagy can bolster cancer cell survival and suppress apoptosis.HPV E6/E7-positive keratinocytes encounter pronounced replicative and oxidative stresses, which are counteracted by autophagy activity. 175Moreover, HPV16 E6/E7 activates autophagy through Atg9B and LAMP1. 176Additionally, HPV11 E6 was found to repress AKT/mTOR and Erk/mTOR, culminating in autophagy activation. 177HPV16 E7 can also triggers autography by inhibiting dual-specificity phosphatase 5. 178 The expression of HPV oncoproteins can activate autophagy through different pathways, which fosters the survival of HPVinfected cells.However, excessively heightened autophagy can induce apoptosis.From this perspective, autophagy is a double-edged sword.For future research, the regulation of autophagy presents a novel avenue for the treatment of HPV-related cervical lesions.

Cell metastasis and invasion
The malignant transformation of histiocytes is characterized by diminished adhesion, heightened metastasis, and increased aggressiveness.The aggressiveness and metastasis of cells hinge upon matrix metalloproteinases (MMPs), specifically MMP-2 and MMP-9, which degrade extracellular matrix (ECM) components, dismantling the histological barricade to tumor cell metastasis.Furthermore, metastasis constitutes a fundamental trait of tumor cells, with numerous studies have highlighting the pivotal role of epithelial-mesenchymal transition (EMT) in tumor metastasis.HPV oncoproteins can degrade the ECM and trigger EMT, thus facilitating the metastasis and invasion of HPV positive cervical cancer cells.
During the process of invasion and metastasis, tumor cells must dismantle the ECM barrier and BM consisting of the intercellular matrix and BM.HPV-associated lesions and malignancies exhibit alterations in the composition and function of the ECM. 179HPVE6 promotes the expression of ADAM10, which regulates cell adhesion and degrades intercellular substances, thereby facilitating the invasion and metastasis of cancer cells. 180MMPs are the enzymes most closely associated with tumor invasion and metastasis.HPV oncoproteins E2 and E7 can upregulate MMP1, MMP9, and MMP12 through the AKT, MEK/ERK, and AP-1 pathways, as well as through direct protein-DNA interactions (which is reviewed in Mendonça et al. 181 ).
EMT denotes the process by which epithelial cells transition phenotypically to acquire an interstitial cell phenotype under specific physiological or pathological conditions.The main morphological features of EMT include the loss of intercellular junction structures in epithelial cells, cytoskeletal remodeling resulting in a shift from polygonal to spindle-shaped fibroblast-like morphology, heightened cellular motility, and resistance to apoptosis.The principal molecular characteristics of EMT encompass the altered expression and depletion of epithelial markers like E-cadherin and occludin, alongside the overexpression of mesenchymal cell markers such as Ncadherin and vimentin.HPV oncoproteins, specifically E6 and E7, are capable of promoting the EMT. 182The loss of E-cadherin expression represents a significant milestone in EMT.Downregulation of E-cadherin expression occurs due to gene mutations, epigenetic gene silencing, and the binding of negatively regulated transcription factors to the CDH1 promoter (which encodes E-cadherin).Several inhibitory proteins, namely, Snail1, Snail2, ZEB1, ZEB2, Twist1, and Twist2, contribute to the suppression of E-cadherin.In HPV-induced cervical cancer, E-cadherin expression is downregulated, while Snail and ZEB1 are markedly upregulated. 183HR-HPV E5/E7 is also implicated in this regulation. 184,185Furthermore, HPV16/18 E7 curtails CDH1 and SNAI1 via DNA methylation. 185The assembly of the actin cytoskeleton is associated with HPV16 E6, rather than HPV18 E6.The downregulation of NHERF1 by HPV16E6 promotes cytoskeleton assembly and cell invasion. 186HPV16 E7 physically interacts with the actin-binding protein gelsolin to regulate EMT via the HIPPO/YAP pathway. 187Additionally, RAS-associated protein Rab31 is upregulated by HPV, further promoting EMT. 188As previously mentioned, the HPV E6 oncoprotein promotes telomerase activity through multiple mechanisms involving epigenetic, transcriptional, and posttranscriptional processes.In HFK/E6E7+ hTERT/hTER cells, a notable reduction in keratin and E-cadherin levels is coupled with a significant elevation in Vimentin and N-cadherin levels, providing evidence for the potential induction of EMT by hTERT/hTERC. 189oreover, HPV viral oncoproteins have been discovered to promote EMT through the regulation of noncoding RNAs.HPV16 E6/E7 upregulates miR-23-3p, thus promoting EMT. 190Moreover, HPV16 E6/E7 upregulates lncRNA SNHG12, which can facilitate EMT through the ERK/Slug/E-cadherin pathway.It has been observed that CircRNA_PVT1 can induce EMT, 191 although its connection with HPV oncoproteins requires further exploration.

HPV genome integration
HPV genes can instigate genome instability through multiple mechanisms, including cell cycle modulation, [192][193][194][195] interaction with DNA damage repair pathways that redirect high-fidelity repair mechanisms to viral episomes rather than the host genome, 196,197 induction of DNAdamaging oxidative stress, and modification of telomere length (which is reviewed in Porter and Marra 198 ).HPV integration into the host genome results from heightened genome instability in HPV-infected cells. 199][205] HPV integration events transpire across all human chromosomes; however, a Chinese study unveiled an excessive concentration of these events on chromosome 19. 2068][209][210] These genes may hold potential as targets for carcinogenesis and intervention.The type of viral integration depends on the HPV genotype, with HPV18 consistently undergoing integration. 211Insertion breakpoints exist in all gene regions of the HPV genome, with E1 and E2 being the most prevalent integration sites.HPV genome integration can manifest as a solitary copy or as multiple tandem repeats of the viral genome within the host genome.Two established models elucidate the integration mechanism.The first is the "looping" model, suggesting HPV integration is mediated by DNA replication and recombination. 212he second model is the "micro-homologies mediated integration model", 208 highlighting two integration mechanisms: FoSTeS (fork stalling and template switching) and MMBIR (microhomology-mediated BIR).The FoSTeS mechanism involves viral genome integration during replication fork stalling.Here, HPV utilizes this pathway and replaces the host genome template to integrate its own.In MMBIR, replication is induced by microhomologiesmediated breaks, enabling HPV genome integration into the host genome during host DNA replication.18 HPV integration augments the expression of viral oncogenes. Iniially, HPV integration disrupts the viral E2 gene, which encodes a transcriptional inhibitor of E6 and E7.213 Subsequently, productive integration culminates in the generation of stable viral-cellular chimeric transcripts, which exhibit greater stability compared with those originating from episomal viral DNA.This depression of transcription and stabilization of fusion transcripts containing E6 and E7 synergistically intensify HPV oncogene expression.214 Integrated tumors frequently manifest elevated levels of E6 splicing, such as E6*I.215 Highly expressed HPV-human fusion transcripts, such as HPV16 E6*I-E7-E1(SD880)-human gene, drive cervical carcinogenesis, culminating in the overexpression of E6*I and E7.216 Furthermore, integration frequently arises in common fragile sites susceptible to tandem repeat formation, with flanking or interspersed host DNA often harboring transcriptional enhancer elements.When coamplified with the viral genome, these enhancers can form super enhancer-like elements that drive robust viral oncogene expression.Even inadvertent integration events can foster viral oncogene expression.217,218 As what we concluded before, HPV E6/E7 partakes in multiple processes, including cell cycle regulation, immune evasion, cell proliferation, and apoptosis. Ithigh expression confers selective growth advantages for cells, 219 thereby sustaining cell transformation and promoting carcinogenic progression.
HPV integration can impact the host genome, leading to genome rearrangements, copy number variations, and gene mutations that can yield aberrant gene expression. 210,220,221These effects encompass amplified expression of cancer-related proto-oncogenes, such as oncogene amplification, and cis-regulatory activation of genes through viral LCR, 222 along with attenuated expression of TSGs, Additionally, HPV integration influences an array of genes linked to cancer progression, as indicated in Table 2. 223 In addition to direct insertions between genes, HPV integration can also affect gene expression via long-range or short-range cis-interactions, involving the expression of various tumor suppressors. 224Moreover, HPV integration can modify gene expression by altering DNA methylation and advancing carcinogenesis progression. 225While most studies suggest that HPV integration activates nearby oncogenes in cervical cancer, a recent study demonstrated that effective virus-cell fusion transcripts typically do not produce endogenous human proteins or alter the expression of nearby genes. 214Subsequent research is essential for investigating the impact of HPV integration on genome structure and expression.

Others
Besides the aforementioned cellular and molecular alterations that drive the malignant transformation of cervical cells following HPV infection, other elements including cellular metabolic reprogramming, oxidative stress, and angiogenesis in the tumor microenvironment significantly contribute to the process.

Cellular metabolism dysregulation
Throughout tumor growth, HPV-infected cells undergo metabolic changes that support their malignant expansion. 232Researcher have demonstrated that HPV E6/E7 can elevate glycolysis. 233Interestingly, Kirschberg's study revealed that HPV8/16 E7 directly and the beta subunit of the mitochondrial ATP-synthase (ATP5B), leading to decreased glycolytic activity but a significant increase in spare mitochondrial respiratory capacity. 234n HPV-induced condylomata acuminata, HPV infection triggers the accumulation of glycogen and escalated glycogen metabolism through hypoxia-inducible factor 1a, crucial for keratinocytes survival and proliferation. 235,236PV E6/E7 promotes aerobic glycolysis in cervical cancer by regulating IGF2BP2 to stabilize m6A-MYC expression, 237 inducing the expression of PKM2, 238 and reducing poly-ubiquitination to stabilize PGK1 protein. 239hese processes yield additional energy sources for tumor proliferation and metastasis.Furthermore, during carcinogenesis or cancer persistence, other metabolic pathways, like glutamine metabolism, undergo modification.Researchers have discerned that E6/E7 exacerbates cell proliferation in a glutamine-dependent manner, 240 providing energy for cancer-related processes.

Oxidative stress
Oxidative stress contributes to carcinoma, as an excess reactive oxygen species can induce oxidative harm to cellular structures and biomolecules, including proteins, lipids, and DNA break, fostering the integration of HPV virus DNA into host genome. 241Cells infected with HR-HPVs can acclimate to oxidative stress by elevating the synthesis of endogenous antioxidants, including catalase, glutathione, and peroxiredoxin, which support the operation of viral oncoproteins. 242

Angiogenesis
Angiogenesis profoundly influences the transition from dysplasia to aggressive cervical cancer.However, the link between HPV infection and angiogenesis remains uncertain.Qiu and colleagues 243 proposed a novel mechanism for HPV16/18 E6-induced cervical cancer progression, implicating "extracellular vesicles-shuttled Wnt7b activating β-catenin signaling," meriting further exploration.
In vitro experiments, E6 was found to activate vascular endothelial growth factor (VEGF)-induced endothelial cell migration and exhibit potent proangiogenic activity. 244

Contributing factors of cervical lesions
Not all HPV infections result in cervical cancer, and the progression of cervical lesions is influenced by various contributing factors, including the vaginal microenvironment and other factors.

Vaginal microenvironment
The cervix resides within the vaginal microenvironment, and modifications in the vaginal microenvironment inevitably impact HPV-related cervical lesions.The vaginal microenvironment encompasses the vaginal microbiome (VMB), the host endocrine system, vaginal anatomy, and local mucosal immunity.Cervicovaginal fluid is a crucial component of the vaginal microecology, containing mucins, antibodies, and various metabolites like lactic acid and sialidase (sld).The VMB, acting as the central element of the vaginal microenvironment, can be categorized into five distinct community state types (CSTs): CST I-III and CST V, predominantly comprising Lactobacillus crispatus, Lactobacillus gasseri, Lactobacillus iners, and Lactobacillus jensenii, respectively.CST IV delineates a heterogeneous group characterized by reduced abundance of Lactobacillus species. 245,246Normative vaginal microbial communities in females typically exhibit low biodiver-sity and are dominated by Lactobacillus.Elevated vaginal microbial diversity often closely correlates with female reproductive system disorders. 247ecently, a close relationship between vaginal microbiota composition and HPV infection has also been extensively documented. 16,248,249The VMB has been found correlated with the severity of cervical lesions.3][254][255] HPV infection can also adversely affect the VMB, 96,256 and these two factors synergistically drive cervical lesions progression.The potential mechanisms are summarized below.First, vaginal dysbiosis (BV) is identified as an independent risk factors for HR-HPV infection. 257Proinflammatory response induced by vaginal dysbiosis-associated bacteria in the vagina and several metabolites such as sld, 258 vaginolysin, 259 and the biogenic amines 260 rupturing the epithelial mucus barrier, making it easier to invade the basal cells.Second, vaginal dysbiosis can influence the clearance and associated with persistent HPV infection.Dysbiosis is characterized by a decrease in Lactobacillus abundance and an overgrowth of species such as Prevotella, Enterococcus durans, Dialister, Lachnospiraceae, and Porphyromonas uenonis, which may be associated with persistent HPV infection. 261,262Lactobacillus crispatus dominated VBM is beneficial for the clearance of HPV, while the effect of CST IV-BV with Lactobacillus.Spp.depletion and other anaerobic bacteria increased is conversed. 263Vaginal dysbiosis influences local mucosal immunity, 264 induced the local immunosuppressive microenvironment, 265,266 and aiding the formation of biofilms, 267,268 hampering virus clearance and leading to persistent HPV infection. 269Among women with persistent HR-HPV infection, an increase in the abundance of Prevotella may influence the development of persistent HPV infection and cervical lesions through host NFκB and C-myc signaling. 270Last, vaginal dysbiosis might propel cervical lesions progression and malignant transformation through chronic inflammation induction and directly activating molecular pathways.Certain pathogenic bacteria associated with vaginal dysbiosis, such as Gardnerella vaginalis and Megasphaera micronuciformis, can increase the expression of E6 and E7, and coculture of SiHa cells with Megasphaera micronuciformis has been shown to decrease p53 and pRb levels and increase the percentage of cells in the S-phase of the cell cycle. 271Phenylactic acid, a phenolic acid phytochemical predominantly produced by Lactobacillus, represses E6/E7 expression while promoting cervical cancer cell migration and via IKK/NF-κB-mediated MMP-9 activation. 272dditionally, coinfections in the vaginal microenvironment, such as Chlamydia trachomatis, 273,274 herpes simplex virus2, Ureaplasma urealyticum, 275 can increase the risk of HPV-associated cervical lesion and cancer; some of these coinfections influence the expression HPV oncogene. 276Researchers have found that the presence of specific anaerobic taxa, including Megasphaera, Prevotella timonensis, and Gardnerella vaginalis, is associated with CIN2 persistence and slower regression, 277 suggesting that VMB composition may serve as a useful biomarker for predicting disease outcome and tailoring surveillance in the future.

Other risk factors
Other endogenous and exogenous contributing factors contribute to the progression of HPV-associated cervical lesions and cervical cancer. 2783][284] Smoking is a common risk factors of cervical cancer, the cigarette smoke components can enhance the expression of HPV16 E6/E7 via EGFR/PI3K/Akt/c-Jun signaling pathway. 285Nicotine can promote HPV-immortalized cervical epithelial proliferation by activating AKT/mTOR pathway, 4EBP1/eIF4E axis, 286 and RPS27a/MDM2/P53 pathway. 287The cigarette smoke condensate can increase the YAP1 activity in human cervical epithelial cells. 130Hormone use has been reported involved in the physiopathology; the ERα, ERβ, PRLR expression levels are increased during the progression of cancer.In vitro, the 60 kDa PRL alone can significantly increase the proliferation of SiHa cells, 288 7β-estradiol, prolactin interacts with HPV and can induce E6/E7 transcript. 289Estrogen also found can induce the genome instability in HR-HPV-infected cervix. 290Contraceptives like Depo-medroxyprogesterone (DMPA) is also found increase the HPV infection, while it seems not accelerate disease progression. 291Immune deficiency, such as the human immunodeficiency virus-infected, seems more likely to have HR-HPV infection than uninfected, attribute to the long-standing immune deficiency. 292,293olycyclic aromatic hydrocarbons are also considered as a cofactor in HPV-mediated carcinogenesis, while the mechanism is worthy further study. 294Interestingly, researchers also found that the chronic stress and diurnal cortisol also play an important role in HR-HPV infection and HPV-associated cervical carcinogenesis. 295Furthermore, dietary factors also appear to play an important role in the animal experiment and human clinical research and both show that diets with low antioxidants (vitamin A, B2, E, and folate) are more likely to develop HPV infections. 296,297

THERAPEUTIC INTERVENTIONS
Currently, the management of precancerous lesions caused by carcinogenic HPV primarily involves surgical interventions, including laser treatment, loop electrosurgical excision procedure, and cold knife conization.
Treatment selection hinges upon lesion severity, HPV type, and the patient's condition.However, some patients continue to experience persistent HPV infection postsurgery, heightening the risk of subsequent recurrence. 298nfortunately, effective treatment drugs for persistent HPV infection are still absent.The primary treatment for cervical cancer entails surgery combined with radiation and chemotherapy.However, women afflicted with positive lymph nodes, recurrent cancer, or metastatic cervical cancer still have a grim prognosis, accentuating the demand for innovative treatment strategies.The following section provides a summary of current treatments and emerging approaches for the management of HPV infection, HPV-related precancerous lesions, and cervical cancer.This includes HPV therapeutic vaccines and genome editing techniques.The primary objectives of this review centers on treatment, with an emphasis on enhancing clinical management for affected patients (Figure 3).

Immunotherapy
The widespread implementation of the HPV vaccine has resulted in a reduction in the prevalence of HPV-associated cervical lesions.However, the vaccine seems to have limited efficacy in treating established HPV infections and cervical lesions.To combat persistent HPV infections and preexisting HPV-related cervical lesions, researchers are developing therapeutic vaccines.Additionally, ongoing clinical trials are exploring immunotherapy drugs such as anti-PD-1/LI antibodies and novel approaches like adoptive cell therapy, which aim to clear HPV infections and inhibit cervical lesions by enhancing the innate and adaptive immune responses.These approaches, when combined with standard-of-care treatments, may offer new treatment options.

Therapeutic vaccines
Unlike preventive vaccines, therapeutic vaccines aim to stimulate the production of CD8+ cytotoxic and CD4+ helper T cell responses.These vaccines mostly target E6/E7 proteins, although some vaccines used in cancer research attempt to target other proteins such as p16 and telomerase (NCT 01462838 and NCT 03946358).The various types of therapeutic vaccines are as follows.

Vectors-based vaccines
0][301][302] The first vacciniabased vaccine used in early cervical cancer is TA-HPV, which demonstrated potent antigen-directed antibody and cytotoxic responses in a completed phase II clinical trial (NCT00002916).Another vaccine, Tipapkinogen Sovacivec, based on modified vaccinia virus Ankara, exhibited efficacy in patients with CIN/III (NCT01022346).
Vvax001, an alphavirus-based vaccine, 303 elicited a vigorous immune response in CIN patients, supporting further clinical evaluation. 304Ongoing clinical trials encompass virous virus-based vaccines, as summarized in Table 3.
Additionally, other viral vectors such as lymphocytic choriomeningitis virus 305 and cytomegalovirus 306,307 are still undergoing preclinical studies and hold promise as potential therapeutic vaccines in the future.However, the generation of antibacterial or antiviral immune responses, as well as the presence of neutralizing antibodies, can pose challenges to the efficacy of viral vector-based vaccines and must be addressed in future research.9][310] Listeriabased vaccines ADXS11-001 have undergone phase I/II clinical to assess their efficacy and safety in HPV+ cervical cancer (NCT02164461 and NCT01266460).A phase III clinical trial for advanced cervical cancer (NCT02853604) was initiated but unfortunately had to be terminated for commercial reasons.Another widely investigated type of vaccine is the lactic acid flora-based vaccine, mostly administered orally for ease of use.Phase I and II clinical studies have been conducted in CINII 311 and CINIII (NCT02195089), but no phase III studies have been carried out.and NCT02426892).Most therapeutic vaccines target E6/E7 proteins.UCPVax, a therapeutic cancer vaccine formulated from distinct peptides originating from telomerase (hTERT, human telomerase reverse transcriptase), has shown safety and potent immunogenic in non-small cell lung cancer and is currently being evaluated in ongoing clinical trials for HPV-related cancer, including cervical cancer (NCT03946358). 312Other ongoing clinical trials for peptide-based vaccines are summarized in Table 3.A limitation of peptide-based vaccines is their suboptimal immunogenicity, prompting the requirement for adjuvants to augment their efficacy.Adjuvants such as CpG oligodeoxynucleotides, 313,314 cobalt-porphyrinphospholipid, 315 and manganese (Mn4+)-doped silica nanoparticles (Mn4+-SNPs) 316 have been found to enhance immune responses.Protein-based vaccines primarily utilize E6/E7 proteins as the main source of antigens.One advantage is that these vaccines contain all epitopes of HLA.However, a potential drawback is their tendency to induce antibody responses rather than CTL responses.Enhancing MHC I presentation is an important area of research, and the utilization of adjuvants and immunostimulant compound such as CpG and GPI0100 could contribute to accomplishing this objective. 317Clinical trials assessing GTL001 (ProCervix) in HPV-infected patients have yielded unsatisfactory results (NCT01957878), while other studies are still ongoing, as summarized in Table 3.

Nucleic acid-based vaccines
DNA-based vaccines: Nucleic acid-based vaccines are safe and easy to manufacture.The DNA-based vaccines have been extensively studied in clinical trials. 318These vaccines entail the introduction of plasmid DNA encoding a desired protein into the host's tissue, enabling its expression and synthesis.However, nucleic acid-based vaccines have limited immunoprototypes, which curtails their utility.0][321][322] A noteworthy example of therapeutic DNA-based vaccines is VGX3100, which comprises two DNA plasmids encoding HPV16/18 E6/E7 proteins.Phase III clinical trials of VGX3100 in CIN II-III have been completed (NCT03185013 and NCT03721978), although the results have not been published yet.These findings offer hope for patients seeking conservative treatments.Other DNA-based vaccines, including GX-188E, NWRD08, and VB10.16, 323 are currently undergoing clinical trials, as summarized in Table 3, with the goal of future clinical implementation.
RNA-based vaccines: RNA-based vaccines have a higher probability of successful transfection compared with DNAbased vaccines because they only need to cross the plasma membrane.However, due to their inherent instability, their application in HPV-related conditions is restricted.Currently, the only clinical trial evaluating an RNA-based vaccine in HPV-related cancer is BNT113 (NCT03418480).

Whole cell-based vaccines
Whole cell-based vaccines entail the loading of HPV antigens into the patient's APCs and reintroducing them into the patient's body.Currently, various types of cells, including B cells, monocytes, DCs, macrophages, engineered mononuclear cells, and engineered red cells, have been used as vectors (NCT02866006, NCT04800978, NCT03870113, NCT05930301, NCT05357898, and NCT04892043).Completed phase I clinical trials have demonstrated the safety and effectiveness of BVAC-C, a vaccine based on B cells and monocytes. 324Nonetheless, the personalized nature and the obstacles related to large-scale manufacturing restrict the applicability of whole cell-based vaccines in the realm of HPV vaccine advancement.

Regulates the immune environment
As previously discussed, HPV infection hampers innate and adaptive immunity through various mechanisms, leading to an immunosuppressive environment that impairs the activity of immune cells.HPV-infected cells can evade immune surveillance and contribute to the progression of cervical lesions and cervical cancer.Thus, reversing the immunosuppressive status has emerged as a crucial therapeutic goal.(Clinical trials about immunotherapy drugs for cervical cancer is summarized in Table 4.)

Immune checkpoint blockades
The programmed death-ligand 1 (PD-L1)/PD-1 axis is crucial for maintaining autoimmune tolerance.PD-L1 functions as the ligand for PD-1, and their interaction leads to the deactivation of T cells.Frequently, tumor cells exhibit elevated PD-L1 expression levels.As previously explained, HPV E6/E7 oncoproteins can upregulate PD-1 expression.Blocking PD-1 has shown promise in HPVinduced cervical cancer. 325In 2018, the United States Food and Drug Administration (US FDA) approved pembrolizumab, an anti-PD-1 antibody, for the treatment of cervical cancer.The clinical trial NCT04712851 is currently assessing the use of pembrolizumab in CIN.Other anti-PD-1 antibodies, including Durvalumab and Nivolumab, remain under evaluation in clinical trials.Another important immune target is CTLA-4, which is expressed on the surface of T cells, which diminishes T cell cytotoxicity upon binding to CD80 or CD86 on APCs.Inhibitors of CTLA-4, such as ipilimumab and tremelimumab, have been extensively investigation in clinical trials, and completed phase I/II trials have shown potent immune activation in metastatic/recurrent cervical cancer.Additionally, other immune checkpoints, including OX40, GITR, TLR3, TIGIT, LAG3, TIM3, CD39, and A2AR, 326,327 as well as relevant agonist and antagonist antibodies, have been investigated in cervical cancer.However, none of them have been approved for use in the context of cervical cancer.Recent preclinical studies have identified CD96 as a potential therapeutic target.Blocking CD96 enhances the efficacy of PD-1 blockade and improves the function of CD8+ T cells, providing a new avenue for research. 328Combining immune inhibitors that target TIGIT, PD-L1, and TGF-β has demonstrated significant antitumor efficacy in preclinical models, 329 and clinical trials investigating this combination are ongoing, indicating a promising direction for research.

Other local immunomodulatory drugs
In addition to the aforementioned targeted drugs, other medications can modulate the immune response, aiding in the clearance of HPV infection and cervical lesion.The Nr-CWS is an effective and safe drugs for treatment of HSIL in Chinese women, 330 and recent studies found it may through stimulating FPR3 to enhance DCs-mediated differentiation, activate the immune response of cervical tissue. 331Additionally, other pertinent studies demonstrate that it can upregulate T cells and inhibit PD/PD-1 pathway, ameliorating the local immune status in HPV infection and CIN patients. 332Imiquimod can bind to Toll-like receptors 7 and 8 of macrophages, producing IFNs, activate the CD8+ T cells.A completed phase II clinical trial has shown that topical treatment with imiquimod is effective of the regression of HSIL 333 (NCT03233412).And the clinical trials have explored the combination of imiquimod and HPV therapeutic vaccines (NCT01957878 and NCT00788164).

Adoptive T cell therapy
ATC involves the ex vivo expansion and manipulation of autologous immune cells to enhance their antitumor activity, followed by their reinfusion into the patient, so that the T cells will target tumor antigens to promote tumor regression. 334ACT have three major categories, tumor-infiltrating lymphocytes (TILs), 335 engineered Tcell receptor T cells (TCR-T), 336 and chimeric antigen receptor (CAR) T cells. 337CAR-T have been approved by US FDA for the therapy of acute lymphocytic leukemia.In the cervical cancer, NCT02280811 and NCT01585428 are the already completed studies about TCR-T and TILs in HPVrelated cervical cancer, which showed potent validity. 338Further pertinent studies are summarized in Table 5.)However, ACT for solid cancers is challenging because solid cancers are less sensitive to T cell-mediated disruption in the tumor microenvironment.In addition, T cells are usually depleted when continuously exposed to their target antigen, despite the ongoing anticervical cancer effect.Induced pluripotent stem cell (iPSC) technology enhances the cytotoxicity of virus-specific CTLs, 339 which can survive long in vivo like young memory T cells, provide sustained tumor suppression, and constitute promising immunotherapy for cervical cancer.

Medication
HPVE6/E7 is the primary pathogenic factor, and there is ongoing investigation into specific antibodies targeting E6/E7.However, the intracellular location of E6/E7 poses a challenge to conventional therapeutic antibodies, hindering their penetration into cells.Recent studies focusing on nanobodies targeting E6/E7 have shown promise in circumventing this limitation.Nonetheless, further research is needed since these studies remain in the preclinical stage.Consequently, there is currently no specific drug available for HPV infection.The ongoing in-depth study of HPV pathogenesis has led to the identification of various pathogenic pathways as potential therapeutic targets for HPV-related cervical lesions.These encompass inhibiting the cell cycle inhibition, suppressing cell proliferation, promoting apoptosis, as well as modulating cellular pathways and regulating the vaginal microenvironment.
In the context of targeted therapy for cervical cancer, in addition to targeted immune checkpoint inhibitors employed in immunotherapy, anti-VEGF antibodies are widely employed in the treatment of cervical cancer.Currently, the standard first-line therapy for recurrent or metastatic cervical cancer involves the combination of chemotherapy and bevacizumab. 356,357Ongoing research is exploring the use of other antiangiogenic drugs and their combinations with different agents, including immune checkpoint inhibitors, in clinical trials (NCT02921269, NCT03074513, NCT03074513, and NCT04551950), with the aim of offering novel clinical options for patients with advanced cervical cancer.
Additional drugs have been utilized in the treatment of HPV infection and cervical precancerous lesions.Recombinant human IFN α−2b, an antiviral drug, has gained approval for HPV infection therapy.Its topical application aids in the clearance of HPV infection by enhancing mucosal immunity. 358,359However, its efficacy in treating cervical lesions appears to be less satisfactory, leading to its usage primarily as an adjuvant therapy. 360REBACIN R is a recently discovered drug that has demonstrated a potent effect on clearing HPV infection.Enriched with the bioactive factor AVF, clinical trials and retrospective studies have confirmed its efficacy in treating HPV infection. 361,362ecent research has also shown that REBACIN R can clear HPV infection by inhibiting the E6/E7 oncogenes. 363Considering the influence of vaginal microbiota on HPV infection and cervical lesions, modulating the VMB appears to be a practical approach for assisting in the clearance of HPV infection. 364A clinical trial (NCT03372395) found that sustained use of vaginal Lactobacillus rhamnosus BMX 54 can restore the vaginal ecosystem and benefit HPV clearance, 365 However, the results seem inconsistent with another study (NCT01599416), 366 highlighting the need for larger randomized studies to confirm these findings.Furthermore, a recent preclinical study demonstrated that the supernatants of lysates and heat-inactivated Lacticaseibacillus casei LH23 can inhibit the expression of HPV E6/E7, thus illustrating the potential anticancer effects of probiotics. 367Traditional Chinese and herbal medicines, such as paiteling, 368 myrtle, 369 and curcumin, 370 have also been investigated in clinical trials for the treatment of HPV infection.Additionally, in preclinical experiments, other Chinese traditional and herbal medicines as well as some natural phytochemicals, such as realgar, 371 securidacasaponins, 372 ficus carica, 373 juglone, 374 can also play the same role.Certain drugs used for treatment of other disease, such as anti-inflammatory drugs, 375 metformin, 376 artesunate, 377 and antifungal agent ciclopirox, 378 may also have broad applications in the clinical management of HPV infection.

Gene editing
As previously stated, the overexpression of E6 and E7 oncogenes closely correlates with the progression of cervical lesions.Consequently, directly knockout of these target genes can effectively inhibit lesion progression.Recent advancements in gene editing technology have realized this prospect.Zinc-finger nucleases (ZFNs), transcription activator-like endonucleases (TALENs), and CRISPRassociated Cas9 endonucleases are three major generations of genome editing tools.Among them, CRISPR/Cas9 is more specific, efficient, and associated with fewer offtarget effects compared with the others. 379Studies have shown that knocking out the E6 and E7 oncogenes using the CRISPR/Cas system can inhibit tumor growth.Targeting the E6 oncogene leads to reactivation of the p53 tumor suppressor pathway, 380 while targeting the E7 oncogene results in the restoration of Rb tumor suppressor pathway. 381Moreover, recent studies have demonstrated that CRISPR can directly hyperactivate p53 and eliminate HPV-driven cervical cancer cells. 3824][385] Currently, there are only two phase I clinical trials investigating the use of TALEN and CRISPR/Cas9 in the treatment of cervical precancerous lesions (NCT03057912 and NCT02800369).

Other nonsurgical treatment
Radical surgery is the preferred treatment option for most patients with early-stage cervical cancer and will not be further discussed here.In cases of precancerous conditions, the excisional technique, including large loop excision of the TZ or cold knife conization, is recommended for patients with CINII-III. 386However, many women may hesitate to undergo these procedures due to concerns about potential preterm labor resulting from cervical incompetence and the risk of cervical adhesions leading to secondary amenorrhea. 387Therefore, this section will primarily focus on other nonsurgical alternatives for the treatment of cervical precancerous lesions.Photodynamic therapy (PDT) is a modern and noninvasive treatment modality employed in the management of both oncological and nononcological conditions.It relies on the local or systemic administration of a photosensitive compound called a photosensitizer (PS).The photocytotoxic reactions induced by PDT occur exclusively within the pathological tissues in the vicinity of PS distribution, enabling selective destruction. 388In the case of HPVrelated cervical lesions, PDT finds wide application in the treatment of precancerous lesions and early-stage cervical cancer. 389Researchers have also discovered that PDT can promote the regression of HPV infection in patients after conization or postmenopause. 390Since the effectiveness of PDT treatment depends on the PS, ongoing research and development of efficient PS can enhance the therapeutic outcomes of PDT, representing a significant area of investigation for future studies.In addition to PDT, other treatments such as cryotherapy, thermocoagulation, 391,392 and focused ultrasound 393,394 are commonly used for cervical precancerous lesions.The selection of specific treatment modality should be predicated upon the extent and scope of cervical lesions.

CONCLUSION
HPV infection imposes significant economic and psychological burdens on patients.The pathogenicity of HPV is closely linked to viral oncoproteins.Microscopic damage The amalgamation of diverse medications, including their coadministration with vaccines, constitutes a burgeoning sphere of inquiry in present clinical research, demonstrating potential as an innovative treatment approach for cervical cancer in the future.ATC therapy, an emerging form of immunotherapy, is currently undergoing clinical trials related to cervical lesions.Encouraging results from its application in the treatment of other diseases have engendered optimism among researchers.Ongoing advancements in gene editing technology, aimed at enhancing its effectiveness, safety, and specificity, hold the potential to enable precise gene therapy for cervical cancer in the future.

A U T H O R C O N T R I B U T I O N S
Jiatian Ye contributed with the manuscript drafting and drawing the graphics.Lan Zheng performed manuscript revision and editing.Yuedong He contributed with the manuscript revision and financial support.Xiaorong Qi performed the manuscript review and editing.All authors have agreed to the final submitted version.

A C K N O W L E D G M E N T S
The authors thank all researchers who contributed to this article.

C O N F L I C T O F I N T E R E S T S TAT E M E N T
The authors declare that they have no competing interests.

D ATA AVA I L A B I L I T Y S TAT E M E N T
Not applicable.

F I G U R E 3
Therapeutic interventions of HPV-associated cervical lesion.Traditional therapy of HPV-associated cervical lesions is surgical treatment combined with radiation or chemotherapy.Up to now, there is no specific drug available for HPV infection.Immunotherapy and gene editing technology is holding the potential to enable precise therapy for cervical cancer in the future.Other nonsurgical treatments, such as photodynamic therapy, cryotherapy, thermocoagulation, and focused ultrasound, are commonly used for cervical precancerous lesions.
Peptide-based vaccines: Peptide-based vaccines are considered safe, stable, and easy to produce.ISA101, consists of HPV-16 E6/E7 synthetic long peptide, has completed phase II clinical trials in recurrent cervical cancer (NCT02128126 TA B L E 3 Therapeutic vaccines for the treatment of HPV-related cervical precancerous lesions and cervical cancer in clinical trials.clinical registration website (https://clinicaltrials.gov), excluding the withdrawal and terminal trials, as of July 2023.NA, data are missing or not publicly available or applicable; Ag, antigen; ORR, objective response rate; mPFS, median progression-free survival; mOS, median overall survival; CR, complete response; PR, partial response; EP, electroporation; C+P, carboplatin and paclitaxel.

TA B L E 4
Clinical trials related to immunotherapy drugs for cervical cancer.clinical registration website (https://clinicaltrials.gov), excluding the withdrawal and terminal trials, as of July 2023.NA, data are missing or not publicly available or applicable.

TA B L E 5
Clinical trials of adoptive T cell therapy for HPV-related cancers.clinical registration website (https://clinicaltrials.gov), excluding the withdrawal and terminal trials, as of July 2023.
to the cervical mucosal epithelium facilitates HPV infection and the invasion of basal cells.Following invasion, the virus synthesizes oncoproteins, utilizes host components for replication, and releases infectious virus particles during basal cell differentiation, thereby completing its life cycle.Viruses can evade the immune response by affecting both innate and adaptive immunity.Failure to promptly clear HPV infection leads to persistent infection and the development of cervical lesions.The expression of viral oncoproteins in host cells disrupts the normal cell division cycle, inducing dysregulating several signaling pathways (such as Notch, Wnt, HIPPO, PI3K/AKT, and RAS pathways) and targeting host proteins involved in cell proliferation, ultimately resulting in uncontrolled cell proliferation.Moreover, HPV can inhibit cell apoptosis and enhance cell metastasis and invasiveness, which are crucial hallmarks of cancer cells.Integration of the HPV virus genome induces alterations in the host genome, representing a significant component of the carcinogenesis process.This integration can result from host chromosome instability due to excessive cell proliferation or the loss of cell proliferation regulation.Host and environmental factors, including the vaginal microenvironment and genetic factors, collectively contribute as significant elements in cervical lesion development.Numerous molecules and signaling pathways involved in the pathogenic mechanism of HPV have potential as therapeutic targets, and there remain several unexplored avenues for future basic research.Commonly used clinical drugs for HPV infection include recombinant IFN and REBACIN R among others.However, the clinical efficacy of these drugs is limited, underscoring the urgent need for research and development of more specific treatments.For cervical precancerous lesions, observation treatment may be appropriate for CINI, whereas CIN II and higher grades necessitate clinical intervention.Common clinical interventions include PDT, cryotherapy, thermal ablation, and ultrasound focusing, among others.The choice of treatment should be determined based on the extent and severity of the lesion.The primary treatment for cervical cancer consists of surgery combined with radiotherapy and chemotherapy.However, patients afflicted with positive lymph nodes, locally advanced disease, or metastatic cervical cancer still face a grim clinical prognosis.The development of therapeutic HPV vaccines holds promise for expanding treatment options for these patients.While HPV DNA vaccines have advanced to later stages of development, most other vaccine types are currently undergoing phase I/II clinical trials.Preliminary clinical trials have demonstrated the effectiveness and safety of the majority of vaccines, warranting large-scale phase III clinical trials and resolution of technical challenges associated with vaccine mass production.Furthermore, immune checkpoint inhibitors represent a significant component of cervical cancer immunotherapy, with PD-L1/PD-1 checkpoint inhibitors being the most extensively studied.Currently, pembrolizumab is approved for advanced cervical cancer, and clinical trials for other similar drugs are also underway.
Major genes related to cancer progression affected by HPV integration.
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